A glimpse of Sun quickly disappears behind clouds...

Michael spent the night at the weather station watching the clouds. The weather had come in as predicted. The snow started after dinner and continued until near midnight. There was patchy cloud through the night and then it came in heavier at about 5 AM. Michael spent the night working on data analysis rather than taking new data.

There were some clouds on the horizon as we went up to the lab so there was hope that we would have a good day of observations. The sky started to clear as the Sun was coming up. Then, about 30 minutes after it rose, it went into a cloud bank and never came out again. The winds were fairly high at the lab and increased throughout the day. The temperature was a balmy -16 C. Of course, it did not feel like that with the winds!

This morning Tom sighted the Brewer on both the Sun and Moon. It was put on-line and a new arctic schedule has been uploaded. The plan is to run it over night and then evaluate the schedule tomorrow. Because of the extreme solar zenith angles of these measurements, the usual Brewer analysis software cannot be used. Specialized software has been developed that can work under these conditions.

Clive and Jennifer made zenith sky measurements with MAESTRO and SPS. There was a problem found with the MAESTRO polarizer so it had to be removed and reinstalled in the proper orientation. Solar checks could not be done yet because there was no Sun.

In the half hour that the Sun was out, Richard M. was able to take one measurement with the DA8. Because the Sun disappeared so quickly, I continued to work on diagnosing the PARIS problem and had some success. I did more measurements of the metrology detector signals and tried blowing some air through the rotary arm mechanism. After this cleaning and then running the interferometer for several hours, it was able to scan at the highest resolution (albeit somewhat intermittently). The plan for tomorrow is to continue the cleaning and see if the performance can be improved further.

SAOZ and DOAS continued their measurements. The dome temperatures have stabilized at about 30 C and so far the windows have stayed frost free. We will keep our fingers crossed that this will continue.

Annemarie took a "day off" at the station today to continue her work on the DOAS data analysis. Her instrument is automated so we kept and eye on the signals and the temperatures while she was away. Because she took the day off, Richard M. and Keeyoon were able to come down to the station for dinner (and to do some laundry). They must really like it up at the lab because they went back up with Michael rather than spend the night at the station.

The daily ozonesonde was launched with the synoptic radiosonde at 23:15 UTC. The Raven balloon didn't get very high, only 17.5 mbar. Richard M. was the winner with a guess of 10.2 mbar.

Today was Richard M.'s birthday and we helped him celebrate with a cocoa banana fudge cake. Debbie the cook really outdid herself with this creation. It came with thick icing, sprinkles, candles, whipped cream and chocolate sauce (because "you gotta go big or go home"). I am not sure that anyone will be able to sleep tonight after all that chocolate and sugar.

Best regards,
Kaley.